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Revision History for A248583

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A248583

The least number m == 1 (mod 6) that is divisible by prime(n).
(history; published version)

#11 by Peter Luschny at Thu Oct 09 15:39:18 EDT 2014

STATUS

proposed

approved

#10 by Farideh Firoozbakht at Thu Oct 09 14:02:18 EDT 2014

STATUS

editing

proposed

#9 by Farideh Firoozbakht at Thu Oct 09 14:01:50 EDT 2014

FORMULA

a(n) = (4*floor((mod(prime(n),6)+4)/6)+1)*prime(n). - Farideh Firoozbakht, Oct 09 2014

MATHEMATICA

Table[p=Prime[n]; (4Floor[(Mod[p, 6]+4)/6]+1)*p, {n, 3, 63}](* Farideh Firoozbakht, Oct 09 2014 *)

STATUS

proposed

editing

#8 by Zak Seidov at Thu Oct 09 11:03:20 EDT 2014

STATUS

editing

proposed

#7 by Zak Seidov at Thu Oct 09 09:18:05 EDT 2014

OFFSET

1,3,1

STATUS

proposed

editing

Discussion

Thu Oct 09

09:18

Zak Seidov: Offset=3, thx!

#6 by Michel Marcus at Thu Oct 09 07:19:24 EDT 2014

STATUS

editing

proposed

#5 by Michel Marcus at Thu Oct 09 07:17:18 EDT 2014

NAME

The least number m == 1 (mod 6) that is divisble divisible by prime(n).

STATUS

proposed

editing

Discussion

Thu Oct 09

07:17

Michel Marcus: typo

07:19

Michel Marcus: offset is 3 ?

#4 by Zak Seidov at Thu Oct 09 05:29:41 EDT 2014

STATUS

editing

proposed

#3 by Zak Seidov at Thu Oct 09 05:28:58 EDT 2014

CROSSREFS

Cf. A002476, A016921.

#2 by Zak Seidov at Thu Oct 09 05:10:11 EDT 2014

NAME

allocated for Zak SeidovThe least number m == 1 (mod 6) that is divisble by prime(n).

DATA

25, 7, 55, 13, 85, 19, 115, 145, 31, 37, 205, 43, 235, 265, 295, 61, 67, 355, 73, 79, 415, 445, 97, 505, 103, 535, 109, 565, 127, 655, 685, 139, 745, 151, 157, 163, 835, 865, 895, 181, 955, 193, 985, 199, 211, 223, 1135, 229, 1165, 1195, 241, 1255, 1285, 1315, 1345, 271, 277, 1405, 283, 1465, 307

OFFSET

1,1

COMMENTS

If a(n) is not prime then a(n)=5*prime(n).

EXAMPLE

a(3)=25 because p=prime(3)=5 and 25= 5*5=1+4*6

a(5)=55 because p=prime(5)=11 and 55= 11*5=1+9*6

a(200)=6115 because p=prime(200)=1223 and 6115=1223*5=1+1019*6.

MATHEMATICA

Table[ChineseRemainder[{0, 1}, {Prime[n], 6}], {n, 3, 200}]

(*or*)Table[p = Prime[n]; If[Mod[p, 6] > 1, 5*p, p], {n, 3, 200}]

KEYWORD

allocated

nonn

AUTHOR

Zak Seidov, Oct 09 2014

STATUS

approved

editing